Device for protecting the collars of rotary kilns



July 14, 1970 G. DEYNAT i 3,520,094

DEVICE FOR PROTECTING THE COLLARS 0F ROTARY KILNS Filed Aug. 5. 1968 m K FIG/1 United States Patent Office 3,520,094 Patented July 14, 1970 U.S. Cl. 52-249 3 Claims ABSTRACT F THE DISCLOSURE This invention provides a kiln, the collar of which is protected by plates on the inner wall of the collar.

The invention relates to a device for protecting the collars of rotary kilns.

In rotary kilns, such as cement kilns, very often some of the brickwork becomes loosened from the casing and drops during operation.

The part of the casing at that place is suddenly subjected to a high temperature. When falls of brickwork occur in line with the hoops and bearing collar, considerable stresses are set up in the collar, leading to its deformation, and sometimes to the breakage of the hoop.

The invention, which obviates this disadvantage, relates to a device for protecting the collars of rotary kilns, characterised in that it comprises a plurality of plates mounted on, and at a certain distance from, the inner wall of the collar, the plates together forming a protective ring parallel with the collar, the gap between the protective ring and the collar being lined with a refractory material.

An exemplary embodiment of the invention will now be described in detail with reference to the accompanying drawings, wherein:

FIG. 1 is a partial section through the kiln casing, in line with a collar, taken along the line I-l in FIG. 2;

FIG. 2 is a plan view, taken along the line II-II 0f FIG. 1, of a device according to the invention, and

FIG. 3 is a section, taken along the line III-III in FIG. 1, of the device according to the invention.

At the places where the bearing sections occur, the casing 1 of the kiln has collars 2 supporting hoops 3. The kiln has an inner lining of refractory brickwork 4. Welded to the inner wall of the collar 2 are regularly distributed chocks or shims 5, some of which are parallel with the kiln axis, the others 6 being perpendicular thereto. A plurality of plates 7 together forming a cylindrical ring having a diameter less than the internal diameter of the collar are applied between the chocks 5, 6. Each plate 7 takes the form of a rectangular section of a cylindrical surface, two sides 8, 9 of which are rectilinear and parallel with the axis, the two other sides 10 being circular and perpendicular to the axis. Circular chocks 11, which have the same thickness as the chocks 5, =6 and are used for positioning the plate 7, are attached to the convex surface thereof adjacent the sides 10.

The side 8 of each plate 7 is formed with orifices 12 which correspond to the chocks 5 and via which the end of each plate is welded thereto. A central slot 13 terminating in a circular orice 14 enables the plate to expand longitudinally. The other end 9 of each plate is curved to engage below the end 8 of the adjacent plate. The join between the ends 8 and 9 of two adjacent plates is filled with-asbestos 17. The assembly of plates therefore forms anl annular belt each element of which can expand in- 5 dependently of the other.

The space 15 between the inner wall of the collar and the'plate is lined with refractory concrete 16 before the plates are put in place. The brickwork 4 forming the inner lining of the casing is disposed on the plates 7. The resulf is a reduction in the internal diameter of the kiln in line with each collar, but the difference in thickness of the lining is progressively made up, and forms no obstacle to the forward movement of the material in the kiln during its rotation.

lIf some of the brickwork covering the device becomes detached, the refractory filling 16 disposed below the uncovered plate 7 remains in place and considerably reduces the temperature to which the collar and hoop are heated.

The elements of the device can readily be replace if they have become excessively deformed by the expansion they have undergone.

Of course, the embodiment disclosed hereinbefore, can be` modified. For instance, the space 15 between the collar and the plates could be filled with some other material than refractory concrete 16, or else merely a gap could be left which would still form a protection for the collar, although a less effective one.

Moreover, the device according to the invention can be used in different installations from rotary kilns, and in a general way in all enclosures subject to elevated temperatures and clad with a refractory lining.

Lastly, in the embodiment disclosed hereinbefore, the device is used exclusively for protecting the collars supporting the hoops or driving rims, but clearly the device could be applied to more extensive portions of the casing.

I claim:

1. A device for protecting the collars of rotary kilns having a metal casing and a refractory lining, comprising a plurality of independent plates mounted on, and at adistance from the inner wall of the collar, the plates together forming a protective ring parallel with the collar, the refractory lining being mounted on the inner face of the protective ring.

2. A protective device as set forth in claim 1, the space between the protective ring and the inner wall of the collar being lled with a refractory material.

3. A protective device as described in claim 1, the plates forming the protective ring being replaceable.

References Cited UNITED STATES PATENTS 2,230,141 1/1941 Heuer 52-249 X 2,635,865 4/1953 Brumbaugh 263-33 3,034,776 5/ 1962 Hennenberger et al. 263-33 3,227,430 1/1966 Vaughan 263-33 3,367,075 2/ 1968 Pierce et al 52-249 PRICE C. FAW, IR., Primary Examiner U.S. Cl. X.R. 

